The present invention relates generally to devices for use with roofs made from sheet metal panels and more particularly, to roof end caps that cover an end of a roof rib formed by two interconnected sheet metal panels.
Sheet metal roofs are typically formed by interconnecting the edges of panels of sheet metal. Generally, one edge of a panel has a male configuration and an adjacent panel has a female configuration so that the edges of adjacent panels can be connected to each other. The connection forms a roof rib defining a seam. The roof rib is typically hollow and has a raised ridge (seam) to allow ease in connecting the sheets together and to allow water to run away from the seam. Since the roof rib has an open end near the apex or ridge of the roof, an end cap is needed to seal the end of the roof rib. End caps are also needed at an upper end of a rib and a lower end wherever roof penetrations, such as air conditioner ducts or chimneys, extend through the roof.
Conventional end caps typically overlay a portion of the end of the roof rib formed by the connection of the two panels cover the end portion of the rib. End caps are usually attached to the roof via rivets or self-tapping screws and some type of sealant or glue. The end caps so affixed form a water-tight seal. Some installations include the use of tape mastic or caulk between the bottom surface of the end cap and the top surface of the roof so that the mastic is compressed between the end cap and the roof. Known end caps are integrally formed from rigid metal or rigid plastic and are only designed to attach to a specific manufacturer's sheet panels.
It is typical that each manufacturer of sheet metal panels has its own unique male and female configuration and edge profile so that separate end caps for each type of roof rib profile must be purchased and stored by building manufacturers and roof installers to accommodate the various different designs. As a further complication, some rigid plastic end caps are designed to only be used with specific left-handed or right-handed rib profiles. Generally, existing end caps are not readily interchangeable such that one end cap can be used for more than one type of roof rib profile.
Some known end caps have a bottom peripheral portion that typically includes small parallel sealing grooves running the entire length of the bottom peripheral surface and all of the sealing grooves are of the same cross-sectional depth. The sealing grooves generally provide increased surface area for the sealant or glue and help contain the sealant under the end cap.
A mismatch of end cap type and rib profile may result in an ineffective seal due to the differences in surface contour. The sealant grooves may be too short to effectively seal gaps between the contour surfaces defining the roof rib profile. This can be exacerbated by contraction and expansion of panel joints during changing climate conditions.
Consequently, there is a need for a type of end cap which enables a reduction of the number and types of end caps inventoried by distributors and sellers. Such an end cap would provide a significant cost reduction. There is also a need for an end cap which can be used for a number of different types of manufacturer's roof rib profile designs and still provide adequate sealing.
Thus, a main object of the present invention is to provide a universal end cap which may be compatible with a number of different types of roof rib profiles.
Another object of the present invention is to provide a flexible end cap that provides improved sealing capabilities along the roof rib profile of varying roof rib profile designs.
It is another object of the present invention to provide a flexible end cap that may better accommodate changes in expansion and contraction due to climatic changes to improve the life and reliability of the roof.